Quadrilateral Graph Tool

Shows a quadrilateral tool within the GraphTool.

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Complete Code

Download file: QuadrilateralGraphTool.pg

POD for Macro Files

PG problem file

Explanation

DOCUMENT();

loadMacros('PGstandard.pl', 'PGML.pl', 'parserGraphTool.pl', 'PGcourse.pl');

Preamble

Load the parserGraphTool.pl macro to be able to use the GraphTool.

$x1 = random(-8, 8);
$y1 = random(-8, 8);
do { $x2 = random(-8, 8); $y2 = random(-8, 8) } until $x2 != $x1 || $y2 != $y1;
do { $x3 = random(-8, 8); $y3 = random(-8, 8) }
    until ($y3 - $y1) * ($x2 - $x1) != ($y2 - $y1) * ($x3 - $x1);
do { $x4 = random(-8, 8); $y4 = random(-8, 8) }
    until ($y4 - $y1) * ($x2 - $x1) != ($y2 - $y1) * ($x4 - $x1)
    && ($y4 - $y1) * ($x3 - $x1) != ($y3 - $y1) * ($x4 - $x1)
    && ($y4 - $y1) * ($x3 - $x2) != ($y3 - $y2) * ($x4 - $x2);

$gt = GraphTool(
    "{quadrilateral, solid, ($x1, $y1), ($x2, $y2), ($x3, $y3), ($x4, $y4)}")
    ->with(
        availableTools => [ 'QuadrilateralTool', 'FillTool', 'SolidDashTool' ]);

Setup

This finds four unique random points and sets up the GraphTool. The line { quadrilateral, solid, ($x1, $y1), ($x2, $y2), ($x3, $y3), ($x4, y4) } creates a quadrilateral with solid line edges and the given four points.

BEGIN_PGML
Graph the quadrilateral with vertices [`([$x1], [$y1])`], [`([$x2], [$y2])`],
[`([$x3], [$y3])`], and [`([$x4], [$y4])`] in that order.

[_]{$gt}
END_PGML

Statement

This asks the student to graph a quadrilateral with the given vertices. The code [_]{$gt} inserts the graph tool.

$alt_text = "A graph of the quadrilateral with vertices ($x1, $y1), ($x2,$y2), "
    . "($x3, $y3),and ($x4, $y4)";
BEGIN_PGML_SOLUTION
The correct answer is

[![$alt_text]!]{$gt}
END_PGML_SOLUTION

ENDDOCUMENT();

Solution

To show the graph with alternate text we use the PGML image construct [! !]{$gt}, where the alternate text is placed within the [! !].